What is the difference between a felony and a misdemeanor under Section 17 of the California Penal Code?

^2. This subdivision states that an offense that can be charged as either a felony or a misdemeanora so-called "wobbler" (People v. Park (2013) 56 Cal.4th 782, 789)is a misdemeanor "[w]hen, at or before the preliminary examination or prior to filing an order pursuant to [Penal Code] Section 872, the magistrate determines that the offense is a misdemeanor, in which event the case shall proceed as if the defendant had been arraigned on a misdemeanor complaint." (Pen. Code, 17, subd. (b)(5).)